Vane pump



July 18, 1944. w. R. TUCKER ET AL 2,354,076

VANE PUMP Filed Feb. 6, 1941 2 Sheets-Sheet l INVENTORS WARREN P.TUCKEP GEORGE AWALDIE 1-L-L MM;

ATTORNEYS y 18, 1944- w. R. TUCKER ET AL 2,354,076

VANE PUMP Filed Feb. 6, 1941 2 Sheets-Sheet 2 IO) M INVENTORS REN R. Tue KER one: MWALDE I V 3 gym P ,4

A TTORNEYS Patented July 18, 1944 UNITED STATES PATENT OFFICE 2,354,076 vans rum Delaware Application February 6, 1941, Serial No. 877,709

Claims.

This invention relates to fluid pumps of the vane type, and more particularly to fluid pumps which are adapted for circulating liquids and for producing pressure with said liquids for actuating various operating elements.

In this invention the flud pump is adapted to pump hydraulic fluid from a storage chamber to a hydraulically actuated device, such as a press, molding machine or other conventional hydraulically actuated mechanisms. There are many types of pumps which are adapted for placing fluids under pressure, including the radial piston type of liquid pump. This type of pump produces high pressure with relatively low power consumption and has been the most efllcient type for use in producing high fluid pressures for actuating mechanical presses requiring high fluid pressures.

In this invention, however, mechanical alterations have been made to a vane type of fluid pump which makes it adaptable for producing high fluid pressures, and particularly, high liquid pressures which are of sufficient value that the pump can be used as the pressure supply mechanism for actuating hydraulic mechanisms. In former vane type pumps considerable diiflculty has been encountered in producing high pressures, since the liquid slip past the vane has been .considerable. There have been attempts to secure the vanes in constant engagement with the cylindrical wall of the cylinder and to increase the volumetric efficiency of vane type pumps when used for liquid delivery. These applicants have produced a mechanism which promotes the maximum efllciency of a vane type liquid delivery pump and which retains the vanes of the pump in constant engagement with the cylindrical wall of the cylinder to prevent liquid slip past the ends of the vanes which are in engagement with the cylinder wall.

It is an object of this invention to provide an improved pump structure for use as a liquid pump.

It is another object of the invention to provide means for retaining the vanes 01! a vane type pump in engagement with the wall of the cylinder.

It is another object of the invention to provide a mechanism in accordance with the foregoing object which resiliently urges the vanes outwardly into engagement with the cylinder wall.

It is another object oi the invention to provide a vane type pump having a plurality of vanes wherein a cylindrical member engages retained in constant engagement with the wall of the cylinder.

It is another object of the invention to provide a vane type liquid delivery pump having means for retainingv the vanes in constant engagement with the walls of the cylinder, and which cylinder is adapted to be moved with respect to the pump rotor in order to change the direction of delivery of the pump.

It is another object of the invention to provide a variable delivery reversible flow liquid pump of the vane type having a mechanism for maintaining th vanes in engagement with the cylinder wall, and which is constructed and arranged for movement of the cylinder with respect the rotor without affecting the mechanism for maintainingthe vanes in constant engagement with the cylindrical wall or the cylinder.

Further objects and advantages will become apparent from the description and the drawings.

In the drawings:

Figure 1 is a longitudinal cross-sectional view taken along line l-l of Figure 2.

Figure 2 is a transverse cross-sectional view taken along line 2-2 of Figure 1.

Figure 3 is an enlarged partial cross-sectional view of one of the vanes of Figure 2, and particularly the vane indicated at A.

In this invention the fluid or liquid pump consists of a casing having passageways H and I2 extending therethrough. Outlet openings l3 and ll are provided in the passageway ll, while out let openings l5 and ii are provided in thepassageway l2. A substantially rectangular membel. 11 forms a cylinder block within which there is provided a cylindrical bore l8 which ex tends transversely of the block l1. This bore l8 forms the cylinder wall of the cylinderoflthe pump. The cylinder block I1 is carried between parallel faces l9 and 20 provided on the easing ill, the parallel faces provided on the cylinder block I! slidably engaging the faces l9 and 20 to permit the cylinder block I l to be reciprocated thereon. A passageway 2| provided in the cylinder block ll communicates with the passageway H, and a passageway 22 provided diametrically opposite the passageway 2| communicates with the passageway l2.

A rotor member 23 has a body portion 24 positioned within the cylinder bore l8. One side of the body portion 24 carries a flanged portion 25 which engages the wall of the cylinder block H, as indicated at 26. An end plate 21 is secured to the vanes in a manner that all or the vanes are t e rot r b dy 4 y eans of t e bolts. 28 and is swung from the center is adapted to engage the opposite face of the cylinder block I1, as indicated at 29.

The flanged portion 25 of the rotor 23 has a hub 35 extending therefrom which is carried by the inner race 3| of a ball bearing 32 which is positioned within a recess provided in the casing I5. The end plate 21 has a hub 34 which carries a bushing 35. The bushing 35 is carried by the inner race 35 of a ball bearing 31 mounted within a recess 39 of the end plate 45 of the casing I5. The end plate 45 is secured to the casing I by means of the bolts 4| and encloses the pumping mechanism within the casing l5. The hub 35, on the flanged portion 25, extends outwardly of the casing I5 and provides a drive shaft 42 which can be suitably connected to a driving mechanism, such as an electric rotor or any other suitable power device.

A conventional oil seal 43 is positioned around the drive shaft 42 and is retained within a recess 44 in the casing l 5 by means of a closure plate 45.

The body 24 of the rotor 23 is provided with a plurality of radial slots 45 in each of which there is positioned a vane 41. The vanes 41 have their outward ends in engagement with the cylindrical bore l8 and which cooperate with the cylindrical bore l5 and the body of the rotor 24 to provide means for pumping fluid between the passageways II and I2. The vanes 41 have their inner ends extending within a central bore 48 provided in the rotor body 24. The bore 45 extends into the flanged portion 25 and a cooperating bore 49 is provided in the plate 21. The vanes 41 are all of equal length and since the cylinder bore I8 is eccentric with respect to rotor body 24 when the pump is in operating position, as indicated in Figure 2, it can readily be seen that the vanes 41 will extend into the bore 48 in the rotor body 24, and that the extending portion of each van will have a different radial length according to the position of the vane with respect to the eccentric positioning of the cylinder bore l8 with respect to the rotor body 24.

In order to retain the vanes 41 in constant engagement with the cylinder bore I 5 a cylindrical pin 55 is positioned within the bore 45 and is of such diameter that the cylindrical surface thereof engages each of the inner ends of the vanes 41. The ends of each of the vanes 41 have an arcuate contour, as indicated at 5|, which are point of the length of the vane so that the arcuate surfaces 5| are portions of a cylinder. Since the vanes 41 are all of equal length it can be seen that the cylindri'cal pin 50 will be arranged concentric with respect to the cylindrical bore l8, and since the end surfaces 5| of the vanes 41 have an arcuate contour which is a portion of a cylinder, it can readily be seen that the vanes 41 will remain in constant engagement with the cylindrical bore l8 at all points throughout their rotation about the pin 55. The pin 55 thus becomes a member which is floated by the inner ends of the vanes 41, which provides a rigid bearing surface upon which the vanes ride in order to mechanically urge the same into constant engagement with the cylindrical bore I 9.

The cylindrical pin 55 is provided with a tapered surface which extends longitudinally thereof, as can readily be seen in Figure I. The inner ends of the vanes 41 are also provided with a tapered surface which extends longitudinally ofthe,,vane. These tapered surfaces on the pin 55' and the vanes 41 cooperate, as indicated at 52, to provide surfaces by which the radial position of the vanes 41 can be altered. Longitudinal or axial movement of the pin 55 forces the vanes 41 inwardly or outwardly according to the direction of movement of the pin 55* to thereby increase or decrease respectively the clearance between the end of th vanes 41 and the cylinder bore I5.

The adjusting means for axially or longitudinally moving the pin 55 consists of a cylindrithe pin 55 extends from the left to the right thereof, viewed in Figure 1, so that movement of the pin 55 to the right will tend to force the vanes 41 outwardly into engagement with the cylinder bore l9. The spring 55 thus provides means for resiliently urging the tapered pin 55 into pressure engagement with the vanes 41. A small hole 53a is provided in the end of the plunger 53 to prevent the plunger from acting as a piston.

An adjusting screw is provided in the end plate 21 and engages a friction button 55 which engages the right-hand end of the tapered pin 55. The adjusting screw 59 is in threaded engagement within the hub 34 of the end plate 21. An inspection plate 5| is provided on the end plate 45 of the casing l5 to permit access to the adjusting screw 59. Means for binding the adjusting screw in position after an adjustment has been made is provided on the hub 34 of the end plate 21 and consists of a portion 62 of the hub which has been separated from the main body thereof by means of a slot 53. A screw 54 extends through the portion 52 and into threaded engagement with the body of the hub 34. When the screw 54 is tightened the flanged portion 52 will bind upon the threads of the adjusting screw 59 to retain the same in its properly adjusted position. A drain opening 55 is provided in the casing 15 to remove liquid or fluid leaking into the casing from the pumping mechanism.

In the structure of the pump of this invention, it will be noted that the tapered pin 55 engages the tapered inner ends of the vanes 41 in such a manner that the spring 55 constantly urges the pin 55 in a direction that the vanes '41 are constantly urged in an outward direction. The adjusting means 59 which opposes the spring 55 engages the opposite end of the tapered pin 55 so that its movement in a rightward direction as viewed in Figure 1 is limited or controlled by the position of the button 55 as regulated by the adjusting screw 59. The force of the spring 55 urging the tapered pin in a rightward direction may thus be directly carried by the button 55 when the pin has moved the maximum amount as controlled by the face of the button.

By the arrangement thus disclosed, it is possible to use any desired spring pressure against the tapered pin 55 for holding the vanes 41 outwardly against the cylinder 2| and yet the exact degree of pressure that is directly applied to the vanes through means of the pin 55 is controlled or regulated by the adjusting means. The vanes are thus held against the surface l5 of the cylinder 2| with a substantially light pressure existing between the surface of the tapered pin 55 and the surface of the cylinder. However, movement of the vanes inwardly toward the center of the rotor is opposed by whatever pressure or force that is developed by the spring 56, so that the vanes 41 cannot collapse toward the center of the rotor until a pressure has been developed in the pump that is of sufficient quantity to cause inward movement of the vanes when applied upon the outer ends thereof to overcome the force of the spring. When such a high pressure is reached, the vanes 41 have complete freedom of movement inwardly to relieve this excess pressure and the tapered pin 50 can move in the leftward direction, as viewed in Figure 1, against the force of the spring 56 to leave engagement with the button 60 momentarily until the excess pressure has been relieved from the pump. As soon as the excess pressure is relieved the spring will again urge the vanes outwardly and retain them in this position with the major force of the spring being carried by the button, or adjusting means, so that the vanes can then run under light pressure between the tapered pin and the surface of the cylinder.

The mechanism just described provides a fluid or liquid pump wherein the fluid flow through the pump is an in-line flow, whereby minimum resistance to fluid flow is obtained and which provides a structural arrangement whereby the fluid can be circulated through the pump without the necessity of passing through a center pintle.

As heretofore described, the flange portion 25 and the end plate 21, together with the body portion 24 form a unit rotor which has the flange portions thereof in sliding engagement with parallel side wall faces 26 and 29 of the cylinder block IT. The unit rotor structure is carried between the ball bearings 32 and 31 in a manner whereb any distortion within the pump caused by production of high pressures therein will be carried directly by the bearings and not by any friction surfaces. While the surfaces 26 and 29 are in close engagement, yet there is always sufficient clearance between these faces to provide a film of lubricating oil therebetween. Any distortion within the pump due to the production of high pressure will be upon an axis at right angles to the axis of the supporting bearings 32 and 31, whereby the movement of the hubs 30 and 34 parallel to the axis of rotation thereof will be absorbed by the bearings 32 and 31, the end plates 25 and 21 merely slide parallel with respect the engaging surfaces 26 and 29.

It is thus seen that this structure provides a pump which has a minimum of friction when developing high pressure and which can develop high pressure without slippage of fluid past the vanes since the vanes are retained in constant engagement with the cylinder bore iii.

The pump, as just described, can be operated as a variable delivery pump, or the fluid flow therethrough can be reversed. A previously described the cylinder block I! is in sliding engagement with the surfaces I9 and 20 of the casing H). The plane of eccentricity of the cylinder bore [8 with respect the rotor 23 is parallel to these surfaces [9 and 20 so that reciprocation. of the cylinder block I! parallel to the surfaces l9 and 20 alters the eccentricity of the cylinder bore l8 with respect the body 24 of the rotor. If the cylinder block I! is shifted from left to right, as viewed in Figure 2, the direction of flow of fluid through the pump will be reversed even though the rotation of the rotor remains continuously in the same direction. Plungers extend through opposite side walls of the casing I0 and engage opposite walls of the cylinder block l1. These plungers are connected to suitable control mechanisms for altering the position of the cylinder block I! with respect the rotor body 24. These control mechanisms may be responsive to the discharge pressure from the pump or can be responsive to mechanisms which indicate the requirement for a reverse of fluid through the pump. However, such mechanisms are common and are well known in the art of variable delivery and reverse flow pumps and therefore further description thereof is not believed necessary since the particular mechanism forms no part of this invention and since any of the well known devices can function to operate the plungers 65 to either vary the flow through the pump or reverse the flow through the same.

While the form of the pump heretofore described is a preferred form, yet there are me chanical modifications thereof which can be developed, and we desire to comprehend within our invention these various mechanical modifications.

Having thus fully described our invention, what we claim as new and desire to secure by Letters Patent is:

1. In a pump, a cylinder, a rotor rotatable therein, reciprocable vanes carried by the rotor,

means within said rotor to cause the vanes to maintain constant engagement with the inner wall of said cylinder while reciprocating in and moving bodily with said rotor comprising a tapered pin in engagement with the inner ends of said vanes, resilient means carried in said rotor acting against the larger end of said pin for constantly forcing said pin in a direction to move the vanes outwardly, and adjustable means carried by said rotor acting against the smaller end of said pin to limit the maximum movement of the pin in said direction.

2. In a pump, a cylinder, a rotor rotatable therein, reciprocable vanes carried by the rotor. means within said rotor to cause the vanes to maintain constant engagement with the inner wall of said cylinder while reciprocating in and moving bodily with said rotor comprising a tapered pin in engagement with the inner ends of said vanes, resilient means carried in said rotor acting against the larger end of said pin for constantly forcing said pin in a direction to move the vanes outwardly, and a screw carried by said rotor engaging the smaller end of the tapered pin to limit the movement of the pin and thereby determine the maximum amount of resilient force applied through the pin to the vanes.

3. In a pump, a cylinder, a rotor rotatable therein, reciprocable vanes carried by said rotor, means within said rotor engaging said vanes to cause the vanes to maintain constant engagement with the inner wall of said cylinder while reciprocating in and moving bodily with said rotor comprising a tapered pin in engagement with the inner ends of said vanes, resilient means carried in said rotor for continuously acting against said pin for constantly forcing said pin in a direction constantly urging the vanes outwardly against said cylinder, and adjustable means carried by said rotor for opposing the movement of said pin as caused by said resilient means to limit or control the maximum movement of the pin in the said direction as caused by said resilient means.

4. In a pump, a cylinder, a rotor rotatable therein, reciprocable vanes carried by'said rotor, means within said rotor engaging said vanes to cause the vanes to maintain constant engagement with the inner wall of said cylinder while reciprocating in and moving bodily with said rotor comprising a tapered pin in engagement with the inner ends of said vanes, resilient means carried in said rotor for continuously acting against said pin for constantly forcing said pin in a direction constantly urging the vanes outwardly against said cylinder, and adjustable means engaging said pin to oppose the motion thereof as caused by said resilient means to limit the maximum movement oi. said pin as caused by said resilient means, said pin being movable away from engagement with said adjusting means against the urge of said resilient means to permit said vanes to move inwardly toward the center of said rotor to relieve excess pressure conditions in said cylinder.

5. In a pump, a cylinder, a rotor rotatable asssme therein, reciprocable vanes carried by said totor. means within said rotor engaging said vanes to cause the vanes to maintain constant enga ement with the inner wail of said cylinder while reciprocating in and moving bodily with said rotor comprising a tapered pin in engagement with the inner ends of said vanes, resilient means carried in said rotor for continuously applying a determined force upon said pin for constantly forcing said pin in a direction to move the vanes outwardly against said cylinder, and adjustable means engaging said pin to oppose the motion thereof to control the maximum movement of said pin in said direction and thereby control the maximum pressure applied by said resilient means to said vanes for holding the samein engagement with said cylinder.

WARREN R. TUCKER. GEORGE A. WALDIE. 

